Added logic to show command line parser help text in console when "--…

…help" argument is specified

AnnoDesigner/App.xaml.cs

@@ -123,7 +123,7 @@ public static string ApplicationPath
             }
         }
 
-        public static object StartupArguments { get; private set; }
+        public static IProgramArgs StartupArguments { get; private set; }
 
         /// <summary>
         /// The DPI information for the current monitor.
@@ -132,7 +132,18 @@ public static string ApplicationPath
 
         private async void Application_Startup(object sender, StartupEventArgs e)
         {
-            StartupArguments = ArgumentParser.Parse(e.Args);
+            try
+            {
+                StartupArguments = ArgumentParser.Parse(e.Args);
+            }
+            catch (HelpException ex)
+            {
+                ConsoleManager.Show();
+                Console.WriteLine(ex.HelpText);
+                Console.WriteLine("Press enter to exit");
+                Console.ReadLine();
+                Environment.Exit(0);
+            }
 
             using var mutexAnnoDesigner = new Mutex(true, MutexHelper.MUTEX_ANNO_DESIGNER, out var createdNewMutex);
             //Are there other processes still running?

AnnoDesigner/ArgumentParser.cs

@@ -1,23 +1,27 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using CommandLine;
+using CommandLine.Text;
 
 namespace AnnoDesigner
 {
-    [Verb("askAdmin")]
-    public class AdminRestartArgs
+    public interface IProgramArgs { }
+
+    [Verb("askAdmin", Hidden = true)]
+    public class AdminRestartArgs : IProgramArgs
     {
         public const string Arguments = "askAdmin";
     }
 
-    [Verb("open")]
-    public class OpenArgs
+    [Verb("open", HelpText = "Opens layout after AnnoDesigner starts")]
+    public class OpenArgs : IProgramArgs
     {
         [Value(0, HelpText = "Input AD file", Required = true)]
         public string Filename { get; set; }
     }
 
-    [Verb("export")]
-    public class ExportArgs
+    [Verb("export", HelpText = "Exports layout to image and exits")]
+    public class ExportArgs : IProgramArgs
     {
         [Value(0, HelpText = "Input AD file", Required = true)]
         public string Filename { get; set; }
@@ -59,11 +63,29 @@ public class ExportArgs
         public bool RenderVersion { get; set; }
     }
 
+    public class HelpException : Exception
+    {
+        public HelpText HelpText { get; }
+
+        public HelpException(HelpText helpText)
+        {
+            HelpText = helpText;
+        }
+    }
+
     public static class ArgumentParser
     {
-        public static object Parse(IEnumerable<string> arguments)
+        public static IProgramArgs Parse(IEnumerable<string> arguments)
         {
-            return Parser.Default.ParseArguments<AdminRestartArgs, OpenArgs, ExportArgs>(arguments).MapResult(x => x, _ => null);
+            var parsed = Parser.Default.ParseArguments<AdminRestartArgs, OpenArgs, ExportArgs>(arguments);
+            return parsed.MapResult<AdminRestartArgs, OpenArgs, ExportArgs, IProgramArgs>(x => x, x => x, x => x, errors =>
+            {
+                if (errors.IsHelp() || errors.IsVersion())
+                {
+                    throw new HelpException(HelpText.AutoBuild(parsed));
+                }
+                return null;
+            });
         }
     }
 }

AnnoDesigner/ConsoleManager.cs

@@ -0,0 +1,92 @@
+using System;
+using System.IO;
+using System.Runtime.InteropServices;
+using System.Security;
+
+namespace AnnoDesigner
+{
+    /// <summary>
+    /// Console manager class for showing console when help text should be shown.
+    /// </summary>
+    /// <remarks>
+    /// Source: https://stackoverflow.com/a/718505
+    /// </remarks>
+    [SuppressUnmanagedCodeSecurity]
+    public static class ConsoleManager
+    {
+        private const string Kernel32_DllName = "kernel32.dll";
+
+        [DllImport(Kernel32_DllName)]
+        private static extern bool AllocConsole();
+
+        [DllImport(Kernel32_DllName)]
+        private static extern bool FreeConsole();
+
+        [DllImport(Kernel32_DllName)]
+        private static extern IntPtr GetConsoleWindow();
+
+        [DllImport(Kernel32_DllName)]
+        private static extern int GetConsoleOutputCP();
+
+        public static bool HasConsole
+        {
+            get { return GetConsoleWindow() != IntPtr.Zero; }
+        }
+
+        /// <summary>
+        /// Creates a new console instance if the process is not attached to a console already.
+        /// </summary>
+        public static void Show()
+        {
+            if (!HasConsole)
+            {
+                AllocConsole();
+                InvalidateOutAndError();
+            }
+        }
+
+        /// <summary>
+        /// If the process has a console attached to it, it will be detached and no longer visible. Writing to the System.Console is still possible, but no output will be shown.
+        /// </summary>
+        public static void Hide()
+        {
+            if (HasConsole)
+            {
+                SetOutAndErrorNull();
+                FreeConsole();
+            }
+        }
+
+        public static void Toggle()
+        {
+            if (HasConsole)
+            {
+                Hide();
+            }
+            else
+            {
+                Show();
+            }
+        }
+
+        static void InvalidateOutAndError()
+        {
+            var type = typeof(Console);
+
+            type.GetField("_out", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic)
+                .SetValue(null, null);
+
+            type.GetField("_error", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic)
+                .SetValue(null, null);
+
+            type.GetMethod("InitializeStdOutError", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic)
+                .Invoke(null, new object[] { true });
+        }
+
+        static void SetOutAndErrorNull()
+        {
+            Console.SetOut(TextWriter.Null);
+            Console.SetError(TextWriter.Null);
+        }
+    }
+}

README.md

@@ -28,6 +28,16 @@ The **Anno Designer** is a standalone windows application that can be used for c
 
 **Download the latest version from the [here](https://github.com/AnnoDesigner/anno-designer/releases/tag/AnnoDesignerv9.2)** (select the .exe file). Run it, and use it to design layouts!
 
+Anno Designer can be started either without any arguments or by specifying one of supported verbs. When started without arguments, empty layout is open.
+
+Run `AnnoDesigner.exe --help` for list of supported verbs
+
+- `open` - opens specified layout file instead of empty layout
+- `export` - exports specific layout file to PNG file and exits
+
+Run `AnnoDesigner.exe <verb> --help` (for example `AnnoDesigner.exe open --help`) for more info about that verb and its arguments.
+
+
 ## Technology
 
 This application is written in C# (.NET Framework 4.8) and uses WPF.